A New Method for Converting Trace Theoretic Specifications to Signal Transition Graphs

The specification of delay-insensitive, asynchronous circuits can be undertaken in a variety of ways. Two methods discussed in this paper involve Trace Theory and Signal Transition Graphs. Trace Theory is used to describe the behavior of circuits in terms of sequences (or traces) of signals. These traces can be composed to express cooperative behavior. However, the resultant composite often suffers from an explosion of states and transitions, which makes it difficult to visualize synchronous and concurrent behavior. By employing Signal Transition Graphs, which are a kind of Petri net, this problem can be ameliorated. In this paper we summarize both Trace Theory and Signal Transition Graphs and describe the advantages we have found in using both interchangeably. The bulk of the paper is devoted to a new technique we have devised for converting Trace Diagrams into Signal Transition Graphs. This technique allows us to readily exploit the benefits of both Trace Theory and Signal Transition Graphs.